Various types of sensing devices are used to produce an electric signal that can be recorded or amplified for stringed instruments. For example, vibrating guitar strings may be sensed for amplification or recording by using an electromagnetic pickup or pickups that are integrated with the guitar. Integrating a sensing device or devices with a guitar can provide consistent sound quality. However, typical electrically amplified guitars are limited to fixed sensing devices positioned under the guitar strings and fastened to the body of the guitar or a microphone or microphones in fixed positions attached to or positioned near the guitar.